Wireless telecommunications networks exist that integrate licensed wireless systems (LWSs) and unlicensed wireless systems (UWSs) and provide seamless transition between the two.
An LWS refers to public cellular telephone systems and/or Personal Communication Services (PCS) telephone systems, for example, providing service over a licensed spectrum. Such licenses are expensive, as is the equipment used to support communications over these licensed frequencies, and this expense is passed on to the user.
A UWS, on the other hand, may comprise, for example, a base station with a physical connection to a landline providing service to a handset using an unlicensed, free spectrum (e.g., approximately 2.4 GHz or 5 GHz). Typically, the quality of service of an LWS is considerably inferior to the quality of service of a UWS. Thus, the user of an LWS pays relatively high fees for relatively low quality service.
Systems exist that integrate an LWS and a UWS, for example, such systems may integrate a Global System for Mobile Communications (GSM) system and an unlicensed mobile access (UMA) system. Such integrated wireless systems (IWSs) allow service to be provided through the UWS when a user is within an unlicensed wireless service coverage area. The user receives the benefit of the relatively inexpensive, high quality communication service. If the user moves outside of the UWS service coverage area, the same communication session can be maintained without interruption by transitioning to the LWS.
FIG. 1 illustrates a system employing UMA technology in accordance with the prior art. System 100, shown in FIG. 1, includes a GSM system 110 and a UMA system 150. The GSM system 110 typically includes a number of mobile switching centers (MSCs) (e.g., 112a and 112b), representing, for example, a core GSM network. Each MSC 112 typically serves multiple base station controllers (BSCs) 114a-114c, each of which, in turn, serves multiple base station transceiver systems (BTSs) 116a-116c. 
The GSM system 110 provides mobile wireless communications to individuals using wireless transceivers, shown for example as user terminal (UT) 118. Wireless transceivers (UTs) include cellular telephones, PCS telephones, wireless-enabled personal digital assistants, wireless modems, and the like. A typical UT may include a display, keypad, and a control circuit. UTs of an IWS typically include two radio transceivers, which may be, for example, a GSM radio transceiver 119 (e.g., operating on a cellular standard), and a UMA radio transceiver 120 (e.g., operating on a wireless local area network (WLAN) standard such as WiFi or Bluetooth). The display may provide a visual indication to a user when the UT is within the service range of the GSM system or the UMA system, the keypad is used in a conventional manner, and the control circuit may be in the form of a processor, a hardwired circuit, a programmable logic device, an application specific integrated circuit, and the like.
As shown in FIG. 1, UMA system 150 is connected to the GSM system 110 through an unlicensed network controller (UNC) 154. The UNC 154 is connected to an MSC (e.g., MSC 112b) of the GSM system 110. Instead of one or more BSCs, MSC 112b has the UNC 154 connected to it. The UNC 154 is connected through an IP network 155 to a plurality of access points (APs), shown, for example, as AP 156. UNC 154 of the UMA system appears to the UT 118 as another cell of the GSM system.
If UT 118 is within the service coverage area of the AP 156, the communication is routed over the higher quality/lower cost UMA system 150. If the UT 118 is not within the service coverage area of the AP 156, the communication is routed over the lower quality/higher cost GSM system 110.
The system 100 can handover a communication between the GSM system and the UMA system. That is, while a communication is in progress the communication can be handed over from routing on the GSM system to routing on the UMA system or vice versa. For example, a user may initiate a communication while moving from one location to another location, and this communication may initially be routed over the GSM system. After arriving at a desired destination, the user may be within the service coverage area of an AP. The communication is then handed over from routing on the GSM system to routing on the UMA system so that the user can take advantage of the higher quality/lower cost of the UMA system. The handover between the GSM system and UMA system is transparent to the user.
The prior art systems typically employ UMA technology and the UMA protocol is hereby incorporated by reference. Such systems have a disadvantage in that difficulties arise in incorporating fixed-terminal devices (FTDs) such as, for example, a fax, a modem, or a regular phone line into current UMA systems. These difficulties have not been adequately addressed.